Dont get caught up in thinking ,"i can fix her" that will only be setting yourself up.Noone can fix anyone! We are all on a differant wave length, and for a reason.The reason is we are all here to learn something, out of the good or bad things that have happened to us!
It takes a certain person to handle someone with issues of ptsd, Depression ect.MOst important is to educate yourself if you choose to be with her.Learn how you can be a help and not a hindrance.
MOving on and trying to find someone w/out any issues is pretty slim.But dont let that keep you from moving on if you dont feel you can hang for the long haul.If you truly love her then try everything you can ,before you give up.Then you'll know you gave it your best shot.Then you will be less likely to feel like you failed.
It takes two people to make it work, and your g/f might not be able at this time to do that.If it's ment to be now, then it's ment to be later.So no worries in giving her time and space if thats what she needs!